Caption: Afterbirth expulsion following childbirth. During pregnancy, the placenta (lower centre) is embedded in the wall of the uterus and attached by the umbilical cord to the developing foetus. Here, the baby has been born, the placenta has been expelled, and the cord is being cut at upper right. The main function of the placenta is to provide the foetus with nourishment, eliminate wastes and to exchange respiratory gases. The placenta, umbilical cord and associated membranes are expelled during the hours after childbirth.